Follow us on Twitter
twitter icon@FreshPatents

Browse patents:
Next
Prev

System and method for detecting, tracking and identifying a gas plume / Bae Systems Information And Electronic Systems Integration Inc.




Title: System and method for detecting, tracking and identifying a gas plume.
Abstract: A system and method for detecting, tracking and identifying a gas plume. The system comprises a processor and a detector in communication with the processor. The detector is effective to detect spectral radiance from a region of interest to detect first and second detected spectral radiance data with a known time difference. A database is in communication with the processor, the database includes a library. The processor is effective to create at least a first image and a second image from the first and second detected spectral radiance data and co-register the first and second images to produce a first co-registered image and a second co-registered image. The processor is further effective to subtract the first co-registered image from the second co-registered image to produce a difference image and generate a cluster region around a difference region in the difference image. The processor is further effective to analyze the spectral radiance from the cluster region to produce a spectral characteristic curve; and correlate the spectral characteristic curve against the library to identify the gas plume. ...


Browse recent Bae Systems Information And Electronic Systems Integration Inc. patents


USPTO Applicaton #: #20100078561
Inventors: Brian A. Gorin


The Patent Description & Claims data below is from USPTO Patent Application 20100078561, System and method for detecting, tracking and identifying a gas plume.

PRIORITY CLAIM

This application claims priority to U.S. Provisional Patent Application No. 61/100,476 filed Sep. 26, 2008, entitled “Temporal Hyperspectral Change Detection Method for Gas Plume Detection, Tracking and Identification” the entirety of which is hereby incorporated by reference.

BACKGROUND

- Top of Page


OF THE INVENTION

1. Field of the Invention

This disclosure relates to image processing and, more particularly, to a system and method for identifying a gas plume in a region of interest.

2. Description of the Related Art

Lethal gas plumes often exhibit very low concentration levels of gaseous effluents. If such gases are released in an environment, it is sometimes quite difficult to detect their presence. For example, some highly toxic gases such as Sarin or VX are not visible to the human eye and have low levels of emissions compared with surrounding environments. Prior art techniques exist for creating a digital image of energy emissions from a region of interest and then determining whether a gas is present in the region. Such techniques may include a “push broom” approach where a single spectral radiance image is taken from overhead, perhaps using an airborne platform, in a single pass. That image is then processed a few hours later. The disclosure relates to an improvement over these prior art techniques.

SUMMARY

- Top of Page


OF THE INVENTION

One embodiment of the invention is a method for detecting and identifying a gas plume. The method comprises receiving, by a processor, a request regarding a region of interest including a gas plume; detecting, by a detector in communication with the processor, spectral radiance from the region of interest to detect first and second detected spectral radiance data; creating, by the processor, at least a first image and a second image from the first and second detected spectral radiance data; co-registering, by the processor, the first and second images to produce a first co-registered image and a second co-registered image; subtracting, by the processor, the first co-registered image from the second co-registered image to produce a difference image; generating, by the processor, a cluster region around a difference region in the difference image; analyzing, by the processor, the spectral radiance from the cluster region to produce a spectral characteristic curve; and correlating, by the processor, the spectral characteristic curve against a library to identify the gas plume.

Another embodiment of the invention is a system for detecting and identifying a gas plume. The system comprises a processor; a detector in communication with the processor, the detector effective to scan a region of interest to detect first and second detected spectral radiance data; a database in communication with the processor, the database including a library; wherein the processor is effective to create at least a first image and a second image from the first and second detected spectral radiance data; co-register the first and second images to produce a first co-registered image and a second co-registered image; subtract the first co-registered image from the second co-registered image to produce a difference image; generate a cluster region around a difference region in the difference image; analyze the spectral radiance from the cluster region to produce a spectral characteristic curve; and correlate the spectral characteristic curve against the library to identify the gas plume.

Yet another embodiment of the invention is a method for detecting and identifying a gas plume. The method comprises receiving, by a processor, a request regarding a region of interest including a gas plume; detecting, by a detector in communication with the processor, spectral radiance from the region of interest in the LWIR range to detect first and second detected spectral radiance data; creating, by the processor, at least a first image and a second image from the first and second detected spectral radiance data, first image and the second image each have two dimensions relating to space and a third dimension relating to wavelength of the spectral radiance; removing, by the processor, elevation effects in the first and second images; co-registering, by the processor, the first and second images to produce a first co-registered image and a second co-registered image, the co-registering includes, for at least one wavelength, lining up temporally adjacent images with the same origin; subtracting, by the processor, the first co-registered image from the second co-registered image to produce a difference image; generating, by the processor, a cluster region around a difference region in the difference image; analyzing, by the processor, the spectral radiance from the cluster region at a particular time to produce a spectral characteristic curve; and correlating, by the processor, the spectral characteristic curve against a gas plume library to identify the gas plume.

BRIEF DESCRIPTION OF THE DRAWINGS

- Top of Page


The drawings constitute a part of the specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.

FIG. 1 is a system drawing of a system for identifying a gas plume in accordance with an embodiment of the invention.

FIG. 2 is a flow chart illustrating a process which could be performed in accordance with an embodiment of the invention.

FIG. 3 is an illustration of two images which could be created in a system in accordance with an embodiment of the invention.

FIG. 4 is an illustration of two images which could be created in a system in accordance with an embodiment of the invention.

FIG. 5 is an illustration of an image which could be created in a system in accordance with an embodiment of the invention.

FIG. 6 is an illustration of two images which could be created in a system in accordance with an embodiment of the invention.

FIG. 7 is a graph showing wavelength and spectral radiance for information which could be generated in accordance with an embodiment of the invention.

FIG. 8 is a graph showing wavelength and spectral radiance for information which could be generated in accordance with an embodiment of the invention.

DETAILED DESCRIPTION

- Top of Page


OF THE PREFERRED EMBODIMENT(S)

Various embodiments of the invention are described hereinafter with reference to the figures. Elements of like structures or function are represented with like reference numerals throughout the figures. The figures are only intended to facilitate the description of the invention or as a guide on the scope of the invention. In addition, an aspect described in conjunction with a particular embodiment of the invention is not necessarily limited to that embodiment and can be practiced in conjunction with any other embodiments of the invention.

The prior art systems described above do not work well in detecting many gases. Gases frequently have low spectral radiance energy emissions and may be hidden in noisy environments including other elements emitting energy at similar wavelengths. In addition, the backgrounds upon which the gases are imposed change spectral radiance due to temperature changes, changes in the atmosphere, solar and thermal changes, time of day etc. and the gases themselves change in temperature (and thus energy emission) over the course of time. In urban environments, the radiant backgrounds themselves provide even more difficulties in detecting and distinguishing gases from the background. Low temperature differences between the gas plume and a noisy radiant background scene often result in unsuccessful gas detection attempts because of the poor signal to noise ratio. Some prior art techniques attempt to deal with these problems by maintaining massive libraries of backgrounds. However, those libraries can not include all potential variants in temperature, time of day etc. without being cost prohibitive. Some techniques attempt to normalize a region of interest but such techniques result in decreased sensitivity. With some gas plumes having very low concentration levels (parts per million or PPM levels) and therefore very low spectral emission coupled with low temperature, differences between the plumes and the backgrounds being small and changing, such decreases in sensitivity may result in loss of detection.

Referring to FIG. 1, there is shown a system 50 for identifying a gas plume in accordance with an embodiment of the disclosure. System 50 includes an airplane or airborne platform 52 with a detector 54 such as a long wave infrared (LWIR) detector focal plane array (FPA) like a mercury cadmium telluride HgCdTe detector FPA integrated with a dispersive grating spectrometer. Detector 54 is in communication with a processor 56 which is, in turn, in communication with a database 58. Detector 54 can be used to scan and detect spectral radiance from a region of interest 60. For example, detector 54 may detect LWIR spectral radiance having wavelengths in the range of 7.5 μm to 13.5 μm though any frequency band may be used and benefit from this disclosure. Many gasses have spectral radiance signatures in the LWIR, VNIR (Visible through Near InfraRed), SWIR (Short Wave Infrared) or MWIR (Mid Wave Infrared Spectral) ranges. As shown, region of interest 60 may include gas plumes 62, 64, 66 of unknown characteristics along with a buildings 68, 70, 72, and 74 and a natural growth such as tree(s) 76.

Referring to FIG. 2, there is shown a process which may be performed by processor 56. As shown, at step S2, a request is received regarding a region of interest including a gas plume. For example, a person on the ground may identify region of interest 60 (FIG. 1).

At step S4, processor 56 controls detector 54 to scan region of interest 60 multiple times with defined time differences, typically on the order of seconds. Referring again to FIG. 1, detector 54 has a field of view (FOV) 78. FOV 78 is scanned (as shown by arrow 80) across region of interest 60 to detect spectral radiance data. The spectral radiance data is used by processor 56 to create two dimensional spatial image data coupled with the spectral radiance data for each spatial pixel to create a three dimensional spectral image cube for region of interest 60. The images need not be displayable to a user and may simply be processed by processor 56. The spatial scanning detects spectral radiance from region of interest 60 at a variety of frequencies f or wavelengths λ. For example if LWIR is used, detector 54 can detect energy information relating to thermally generated spectral radiance. Each scan of region of interest 60 by detector 54 results in processor 56 creating a three dimensional image—two dimensions for space (i.e. X and Y coordinates) and one dimension for wavelength λ. For example, the three dimensional image may be represented as 512 pixels X by 512 pixels Y by 100 pixels λ. Region of interest 60 is scanned multiple times in a short period (e.g. over a few seconds or minutes) while airborne platform 52 passes over region of interest 60. Alternatively, a single field of view 78 may cover the entire region of interest 60 and then that field of view is scanned for each wavelength of interest. A series of temporally adjacent three dimensional images are now created relating to region of interest 60—one for each scan 80.

The scanning could be performed using, for a example, systems available from BAE SYSTEMS such as SPIRITT (Spectral Infrared Remote Imaging Transition Test bed) systems. The LWIR hyperspectral detector as part of SPIRIT, for example, can produce 186 longwave wavelength images for each of the spatial 512 pixels X by 512 pixels Y at 400 frames per second. SPIRITT has five separate sensors with a common aperture so that sensor imagery are all co-registered. Data from multiple sensors within SPIRITT can be fused or used for measuring extended spectral signatures. SPIRITT operates on an inertially stabilized platform resulting in high quality images.

Detection is optimized by collecting light or energy with a large unobstructed fore-optic aperture and focusing the energy with high performance imaging spectrometer optics coupled to focal plane arrays (FPAs) with low-noise electronics. To keep this well-constructed image plane fixed on the FPAs during image integration, a high-performance servo stabilization system controls gimbal motion and enables scanning using high-performance fiber-optic gyros.

Target discrimination is performed in the SPIRITT Hyperspectral Digital Signal Processor (HDSP) weapons replacement assembly (WRA). This assembly receives the extremely high-quality hyperspectral image data from the low-noise focal plane electronics and removes detector artifacts. This step helps ensure that the target discrimination algorithms do not generate false alarms from detector fixed-pattern noise. The HDSP discrimination algorithms operate on the corrected uniform hyperspectral image data. Target cueing is performed by integrating the data from the discrimination algorithms and the geo-location data. Precise geo-location data is developed from the gimbal angle, Inertial Navigation System/Global Positioning System (INS/GPS) and the SPIRITT sensor geometry knowledge.




← Previous       Next →
Advertise on FreshPatents.com - Rates & Info


You can also Monitor Keywords and Search for tracking patents relating to this System and method for detecting, tracking and identifying a gas plume patent application.

###


Browse recent Bae Systems Information And Electronic Systems Integration Inc. patents

Keyword Monitor How KEYWORD MONITOR works... a FREE service from FreshPatents
1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored.
3. Each week you receive an email with patent applications related to your keywords.  
Start now! - Receive info on patent apps like System and method for detecting, tracking and identifying a gas plume or other areas of interest.
###


Previous Patent Application:
Gas detector
Next Patent Application:
Hidden sensors in an electronic device
Industry Class:
Radiant energy
Thank you for viewing the System and method for detecting, tracking and identifying a gas plume patent info.
- - -

Results in 0.06053 seconds


Other interesting Freshpatents.com categories:
Software:  Finance AI Databases Development Document Navigation Error

###

Data source: patent applications published in the public domain by the United States Patent and Trademark Office (USPTO). Information published here is for research/educational purposes only. FreshPatents is not affiliated with the USPTO, assignee companies, inventors, law firms or other assignees. Patent applications, documents and images may contain trademarks of the respective companies/authors. FreshPatents is not responsible for the accuracy, validity or otherwise contents of these public document patent application filings. When possible a complete PDF is provided, however, in some cases the presented document/images is an abstract or sampling of the full patent application for display purposes. FreshPatents.com Terms/Support
-g2-0.1195

66.232.115.224
Browse patents:
Next
Prev

stats Patent Info
Application #
US 20100078561 A1
Publish Date
04/01/2010
Document #
File Date
12/31/1969
USPTO Class
Other USPTO Classes
International Class
/
Drawings
0




Follow us on Twitter
twitter icon@FreshPatents

Bae Systems Information And Electronic Systems Integration Inc.


Browse recent Bae Systems Information And Electronic Systems Integration Inc. patents



Radiant Energy   Invisible Radiant Energy Responsive Electric Signalling   Infrared Responsive   With Means To Analyze Uncontained Fluent Material  

Browse patents:
Next
Prev
20100401|20100078561|detecting, tracking and identifying a gas plume|A system and method for detecting, tracking and identifying a gas plume. The system comprises a processor and a detector in communication with the processor. The detector is effective to detect spectral radiance from a region of interest to detect first and second detected spectral radiance data with a known |Bae-Systems-Information-And-Electronic-Systems-Integration-Inc
';